The Xy wing quoted by clement is of a type that is moderately easy to spot. The elements of the XY are in col 8 in what I think of as a 'tight triad' but the 34 in box 6 gives the same numerical tight triad but not in a straight line so it becomes an Xy wing. But the two 34s also form a w wing that gives almost the same subsequent moves! so the XY and W wings are highly related in this example!